Insert for railing top rail



FIG. 1 is a perspective view of our insert for railing top rail;

FIG. 2 is an end view thereof,

FIG. 3 is a left side view thereof, the right side being a mirror image thereof;

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof.

The break lines depict bounds of the claim. The portion between the break lines forms no part of the claimed design. 

CLAIM The ornamental design for an insert for railing top rail, as shown and described. 